Supporters of Syriza at a rally in Athens. 'A Syriza government could spur on other anti-austerity forces across the continent.' Photograph: Petros Giannakouris/AP

Another war looms in Europe: waged not with guns and tanks, but with financial markets and EU diktats. Austerity-ravaged Greece may well be on the verge of a general election that could bring to power a government unequivocally opposed to austerity. Momentous stuff: that has not happened in the six years of cuts and falling living standards that followed the collapse of Lehman Brothers.

But if the radical leftist party Syriza does indeed triumph in a possible snap poll in the new year, there will undoubtedly be a concerted attempt to choke the experiment at birth. That matters not just for Greece, but for all of us who want a different sort of society and a break from years of austerity.

What misery has been inflicted on Greece. One in four of its people are out of work; poverty has surged from 23% before the crash to 40.5%; and research has demonstrated how key services such as health have been hammered by cuts, even as demand has risen. No wonder the country has experienced a political polarisation that has prompted comparisons with Weimar Germany. The neo-Nazi Golden Dawn – which makes other European rightist movements look like fluffy liberals – at one point attracted up to 15% in the polls; though still a menace, its support has thankfully subsided to half that.

But unlike many other European societies – with the notable exceptions of Spain and Ireland – fury and despair with austerity has been channelled into the ranks of the populist left. After years on the fringes of Greek politics, Syriza only became a fully fledged party in 2012, and yet it won Greece’s elections to the European parliament earlier this year. The latest opinion polls give Syriza a substantial lead over the governing centre-right New Democracy party. A radical leftwing government could well assume power for the first time in the EU’s history.

After years of social ruin, Syriza is offering Greeks that precious thing: hope. Although it has shifted from demanding an immediate cancellation of debt, it is demanding a negotiated solution. It has conjured up the example of a European debt conference to wipe away a portion of the debt, as happened with Germany in 1953. Syriza’s manifesto proposes that repayment of debt could come through economic growth, rather than from budget cuts. It wants a European new deal backed up by an investment bank; an all-out war against the tax avoidance endemic in Greek society; an emergency employment programme; a raised minimum wage; and the restoration of collective bargaining. In alliance with anti-austerity forces such as Spain’s surging Podemos party, Syriza wants the EU to abandon crippling austerity policies in favour of quantitative easing and a growth-led recovery.

There’s one small catch: the determined opposition of the establishment in both Greece and the EU. Greece was ruled by a hard-right junta, the colonels’ regime of 1967-74, and there is still clearly anti-leftist sentiment deeply embedded in the state. The police have been infiltrated by Golden Dawn elements, with accusations that they have tortured anti-fascist protesters. The head of the bank of Greece has warned of “irreparable damage” to the economy if there is a change of course. Some form of coup – even if more subtle than that executed by the colonels in 1967 – cannot be ruled out.

And then there’s the president of the European commission, Jean-Claude Juncker, a man who hardly has an inspiring democratic mandate and is best known for questions over his former country’s tax avoidance policies, who has already made it clear that the Greek people should not vote the wrong way. “I think that the Greeks – who have a very difficult life – know very well what a wrong election result would mean for Greece and the eurozone,” he has said. “I wouldn’t like extreme forces to come to power.” There are rumours that, if Syriza does win, Greece could be deprived of all EU funding. Apocalyptic talk of capital flight and bank runs abound. Markets and elite politicians alike have their guns pointed at the Greek electorate.

Syriza’s leadership does have its leftwing critics, though. Those on the party’s left look to the likes of Costas Lapavitsas, an economics professor at London’s School of Oriental and African Studies, who believes its programme is impossible within the confines of monetary union. He believes that Syriza’s attempt to transform the EU is naive, but allows the party “to tell people you can have your cake and eat it”, not least given that most Greeks do not wish to be ejected from the eurozone – even after everything that has happened to them.

A confrontation looms between a Syriza government and the EU, he believes, and Greece will be hammered with blackmail and possible “deadly pressure” from the European Central Bank which could strangle the financial system in days. “Grexit” may happen, whether Syriza’s leaders want it or not.

That’s why Greece desperately needs solidarity. Firstly, there’s a point of principle: to defend sovereignty and democracy from attack, whether from within or without. But a Syriza government could spur on other anti-austerity forces across the continent. It is conceivable that Podemos could assume power in Spain later in 2015. The likes of Die Linke in Germany – the country at the very heart of the EU’s austerity drive – could be given a boost, too.

Here in Britain, Syriza already represents a warning to Labour. The explosion in Syriza’s popularity has everything to do with Labour’s sister party in Greece, Pasok, coming to power and unleashing austerity on its own supporters. The consequence? Pasok is now on about 5% in the opinion polls. In Britain, some polls already have the Greens on up to 9%, and that’s before a Labour government that implements cuts has assumed power. Despite the British elite’s deficit-mania, polling by Ipsos Mori finds that while 27% believe Labour “gets the balance about right” when it comes to spending, 26% believe the party will cut too much. A Syriza victory could strengthen those who wish Labour to offer a genuine alternative – or, alternatively, if the first-past-the-post electoral system finally shatters, Britain’s own Syriza-style party.

So 2015 could finally be the year when austerity meets its reckoning across the continent. Or it could be the year that a democratic challenge to economic madness was strangled to death. It is a game of high stakes in which the futures of millions of people could be decided.